1. Field of the Invention
The present invention relates to an optical scanning type observation apparatus and a method for operating the optical scanning type observation apparatus, and in particular to an optical scanning type observation apparatus for scanning an object to generate an image and a method for operating the optical scanning type observation apparatus.
2. Description of the Related Art
For endoscopes in a medical field, various techniques for reducing a diameter of an insertion portion inserted into a body cavity of a subject are proposed to reduce a burden on the subject. As an example of such techniques, a scanning type endoscope not having a solid image pickup device at a part corresponding to the insertion portion described above and an observation apparatus configured having the scanning type endoscope are known.
More specifically, the observation apparatus having the scanning type endoscope is configured, for example, to two-dimensionally scan an object in a scan pattern set in advance by causing a distal end portion of an illumination fiber for guiding illuminating light emitted from a light source to be swung, receive return light from the object by a receiving fiber arranged around the illumination fiber, and generate an image of the object based on the return light received by the receiving fiber. As such that has a configuration similar to the configuration of the observation apparatus, for example, an optical scanning type endoscope apparatus disclosed in Japanese Patent Application Laid-Open Publication No. 2010-142482 is known.
More specifically, Japanese Patent Application Laid-Open Publication No. 2010-142482 discloses a configuration of an optical scanning type observation apparatus provided with such a light supply fiber that a position of an emission end in a state of not being bent is set at a predetermined reference point, the configuration being for performing such control that a scanning period during which a distal end of the light supply fiber is caused to be displaced along a spiral-shaped displacement route, from the predetermined reference point to a maximum amplitude, and a damping period during which the light supply fiber is caused to be displaced from the maximum amplitude to the predetermined reference point are alternately repeated. Further, Japanese Patent Application Laid-Open Publication No. 2010-142482 also discloses a configuration for performing radiation of white color light to an observation target area and generation of a pixel signal during the scanning period.